GB2190887A

GB2190887A - Motor vessel drive

Info

Publication number: GB2190887A
Application number: GB08612752A
Authority: GB
Inventors: Terence Charles Holmes
Original assignee: Individual
Current assignee: Individual
Priority date: 1986-05-27
Filing date: 1986-05-27
Publication date: 1987-12-02
Anticipated expiration: 2006-05-27
Also published as: GB2190887B; GB8612752D0

Abstract

A motor vessel drive in which the height and thrust angle of a propeller 32 is adjustable independently comprises: a shaft 2 journalled in the vessel; a lower pivot point 6 fixed in the vessel; an upper pivot point 10 adjustable fore-and- aft in the vessel; a tail shaft support 20,29 having a lower pivot 18, a upper pivot 24 and a tail shaft 31; a lower link 15 extending between the lower pivot point 6 and the lower pivot 18; an upper link 21 extending between the upper, adjustable pivot point 10 and the upper pivot 24; an intermediate shaft 34 between the vessel shaft 2 and the tail shaft 34; an actuator 12 for moving the upper pivot point 10 fore-and- aft for inclination of the propeller 32; and actuator 14 for moving the lower link 15 up and down to adjust the height of the propeller. The adjustable upper pivot point 10 may be replaced by an extendable upper link 21. <IMAGE>

Description

SPECIFICATION Motor vessel drive The present invention relates to a motor vessel drive.

Asimpleform of a motor vessel drive isa propeller attached to a conventional Iy jou rna I led propeller shaft. For high performance vessels, this has the disadvantagethatthe height and up-and-down direction of thrust of the propeller can not be adjusted. Such adjustment is desirablefortrimming the vessel to reduce its wetted area.

Adjustable drives do exist. In particular, the so-called Arneson drive consists of a universal joint attached between the aft end of a conventionally journalled shaft and an extension shaft extending beyond the transom of the vessel. Adjacentthe propeller, a plummer block on the aft end ofthe extension shaft, is connected via two adjustable length struts to two points on the transom on opposite sides ofthe shaft line and above it.

Adjustment of the struts together swings the shaft and propeller about the universal joint. Such adjustment alters both height and up-and-down direction of thrust simultaneously. It is not possible for them to be adjusted independently using this drive.Afurtherfeature of this drive is that adjustment of the struts in opposition changes the direction ofthrust in the steering mode, whereby the vessel can be steered.

Another drive is a conventional "out-drive", in which a drive shaft above the propeller is connected to a universal joint connected in turn to bevel gearing. This drives a vertical, in use, shaft driving a short propeller shaft via further bevel gearing. The universal joint provides the facility for steering and the vertical shaft enables the propeller shaft and thrustto be substantially horizontal whilst below the foot of the transom. However, again independent adjustment of up-and-down thrust direction and height is not possible.

The object of the present invention is to provide a drive having improved adjustability.

According to the present invention, there is provided a motor vessel drive comprising: a primaryshaftjournalled in the vessel; a lower pivot pointfixed to the vessel adjacentthe outboard end ofthe primary shaft; an upper pivot point adjustable fore and aft above the lower pivot point; a lower link extending aft from the lower pivot point; an upper link extending aft from the upper pivot point; an intermediate shaft extending aft from the primary shaft; a tail shaft extending aft from the intermediate shaft and carrying a propeller; a pair of universal couplings, one between the primary and intermediate shafts and the other between the intermediate and tail shafts;; tail-shaft support meansjournallingly supporting the tail shaft and having upper and lower pivots connected respectively to the after ends of the upper and lower links; means for lifting or lowering the links and tail-shaft support means whereby the propeller is lifted or lowered with respect to the vessel without alteration ofitsdirection of th rust; a nd means for adjusting the fore and aft position of the upper pivot point whereby the propellerthrust angle is adjusted substantially independently of its height.

In an alternative, the length of the upper link is adjustable and the upper pivot point is fixed.

Preferably the upper pivot point, lower pivot point and forward universal joint are substantially aligned above each other (although small amount of non-alignment is caused by adjustment of the upper pivot point). Similarly the upper pivot, the lower pivot and the after universal joint are substantially aligned above each other. Where these alignments are not good, a plunging coupling maybe provided in one of the shafts.

Preferably the lower pivot point and the lower pivot are arranged immediately above the universal couplings. Again, where this is not so a plunging coupling may be arranged for accommodating shaft plunge on fore and aft adjustment ofthe upper link forth rust angle adjustment. Conveniently the lower pivot point is provided at the foot of the transom.

The upper and lower links are preferably wishbones with their forward ends laterally spaced, each link having a pairofcoaxial pivotal connections to the respective pivot points. The after ends ofthe links may also be laterally split.

The drive preferably includes steering means. This may be a rudder hung on thetail-shaftsupport means or the latter may comprise two parts pivotally connected about an upright rudder axis passing through the after universal coupling. In the latter case, the after part ofthe tail-shaft support means preferably includes rudder elements for steerage without drive of the propeller.

To help understanding ofthe invention, a specific embodiment thereof will now be described byway of example and with reference to the accompanying drawings, in which:- Figure lisa side view of a motor vessel drive of the invention, Figure2 is a cross-sectional view on the line ll-ll in Figure 1; and Figure 3 is a cross-sectional view on the line Ill-Ill in Figure 1.

The vessel, whose hull 1 is partly shown, has an in board engine- notshown.A primarydrive shaft2 extends through the hull via conventional journals and seals. The after end ofthe primary shaft 2 terminates in a universal coupling 3, immediately below and behind the transom 4. On the foot of the transom is bolted a lower-pivot-point member 5, having a pairofcoaxial pivotpins6equallylaterally spaced on either side of the vessel's central plane.

Upstanding between the pivot pins 6 is a pivot-points spacing member7 having a pair of laterally spaced flanges 8. Each has an arcuate slot9 close to its upper edge and centred on the pivot pins 6. An upper-pivot-point shaft 10 extends through the slots 9 and is centrally connected to the actuating shaft 11 of a hydraulic ram orscrewactuatorl2, mounted in-board of the transom. The upper end of the pivot-points spacing member is fixed to the transom. Between the flanges 8 extends a securing bolt 13 for a second hydraulic ram or screw actuator 14 extending downwardly.

A pair of lower-link arms 15 are pivotally connected at their spaced forward ends 16 to the pair of pins 6. Intermediate their ends they are connected together and pivotally connected to the actuating shaft 17 of the actuator 14. The after ends of the arms 15 are joined together and pivotally accommodated via a pivot pin 18 in a slot 19 in a non-steering support member20.A pairof upper-linkarms 21 are pivotally connected at their spaced forward ends 22 to the shaft 9 on respective opposite sides ofthe flanges 8. The after ends 23 ofthese arms 21 are pivotally connected to respective studs 24 on opposite sides of the non-steering support member 20. The arms are retained on the shaft 10 and studs 24 by conventional means.

The non-steering support member 20 has upper and lower wrists 25,26 between which fixedly extends a steering axis rod 27. This journallingly carries a forward extension 28 of a steering support member 29, the extension being captive axially of the rod 27 between the wrists 25,26. The steering support member has upper and lowergeneraily planar rudder surfaces 29U,291, the upper of which is fixed to the forward extension 28. A hub 30 is arranged between the rudder surfaces 29U,291 and journallingly carries a tail shaft 31. A propeller 32 is attached to the after end ofthe tail shaft 31 and a second universal coupling 33 is attached to the forward end thereof. An intermediate shaft 34 extends between the couplings 3,33 fortransferring drive from the primary shaft to the tail shaft.The couplings are conveniently of the cup and cross pin type to provide a small amount of axial plunge.

To adjustthe propeller up or down, the actuator 14 is operated. The upper arms 21 and the lower arms 15 are of equal length; and the pivot pins 6/shaft9 separation is the same as the pivot pin 18/studs 24 separation. Thus the tail shaft moves parallel with itself on operation of the actuator 14.

To adjustthe inclination to the vessel's water line of the propeller, the actuator 12 is operated, to move the upper end of the support members 20,29 fore and aftvia thetop link arms 21 whilst the lower end of the support members remains held in the same position bythe lower arms 15.

For steering, a tiller member 35 is pivoted on an upper extension 36 of the rod 27. It is provided with lugs 37 bearing on opposite sides ofthe upper rudder surface 28. The member 34 extends laterally on both sides of the rod extension 36 and is controlled by respective steering lines 37 attached to its free ends and operated by a conventional steering mechanism.

Claims

1. A motorvessel drive comprising: a primary shaftjournalled in the vessel; alowerpivotpointfixedtothevessel adjacentthe outboard end ofthe primary shaft; an upper pivot point adjustable fore and aftabove the lower pivot point; a lower link extending aft from the lower pivot point; an upper link extending aftfrom the upper pivot point; an intermediate shaft extending aft from the primary shaft; a tail shaft extending aft from the intermediate shaft and carrying a propeller; a pair of universal couplings, one between the primary and intermediate shafts and the other between the intermediate and tail shafts;; tail-shaft support means journallingly supporting the tail shaft and having upper and lower pivots connected respectively to the after ends of the upper and lower links; means for lifting or lowering the links and tail-shaft support means whereby the propeller is lifted or lowered with respect to the vessel without a Iteration of its direction of thrust; and means for adjusting the fore and aft position ofthe upper pivot point whereby the propellerthrust angle is adjusted substantially independently of its height.

2. A motor vessel drive comprising: a primaryshaft journalled inthevessel; a lower pivot pointfixed to the vessel adjacentthe outboard end ofthe primary shaft; an upper pivot point fixed to the vessel above the lower pivot point; alower-fixed Iength-Iinkextendingaftfromthe lower pivot point; an upper- adjustable length- link extending aft from the upper pivot point; an intermediate shaft extending aft from the primary shaft; a tail shaft extending aft from the intermediate shaft and carrying a propeller; a pair of universal couplings, one between the primary and intermediate shafts and the other between the intermediate and tail shafts;; tail-shaft support meansjournallingly supporting the tail shaft and having upper and lower pivots connected respectively to the after ends of the upper and lower links; means for lifting or lowering the links and tail-shaft support means whereby the propeller is lifted or lowered with respect to the vessel without alteration of its direction ofthrust; and means incorporated in the upper, adjustable-length linkfor adjusting the fore and aft position of the upper pivot whereby the propeller thrust angle is adjusted substantially independently of its height.

3. A motor vessel drive as claimed in claim 1 or claim 2, wherein the upper pivot point, lower pivot point and forward universal joint are substantially aligned above each other.

4. Amotorvessel drive as claimed in claim 1, claim 2 or claim 3, wherein the upper pivot, the lower pivot and the after universal joint are substantially aligned above each other.

5. A motor vessel drive as claimed in any preceding claim, including a plunging coupling provided in one of the primary shaft, the intermediate shaft and the tail shaft.

6. A motor vessel drive as claimed in any preceding claim, wherein the lower pivot point and the lower pivot are arranged immediately above the universal couplings.

7. A motor vessel drive as claimed in any preceding claim, wherein the lower pivot point is provided at the foot of the transom.

8. A motor vessel drive as claimed in any preceding claim, wherein the upper and lower links are wish bones with their forward ends laterally spaced, each link having a pair of coaxial pivotal connections to the respective pivot points.

9. A motor vessel drive as claimed in claim 8, wherein the after ends ofthe links are laterally split.

10. Amotorvessel drive as claimed in any preceding claim, including steering means.

11. A motorvesse drive as claimed in claim 10, wherein the steering means is a rudder hung on the tail-shaft support means.

12. Amotorvessel drive as claimed in claim 10, wherein the tail shaft support means comprises two parts pivotally connected about an upright rudder axis passing through the after universal coupling, the after ofthe two parts providing the steering means.

13. A motor vessel drive as claimed in claim 13, wherein the after part ofthe tail-shaft support means includes rudder elements for steerage without drive ofthe propeller.

14. A motor vessel drive as claimed in claim 1 or any one of claims 3 to 13 as appendantthereto, including a pivot points spacing memeberfixed to the vessel and having the lower pivot point at a lower end end thereof and a slotthereabove defining the upper pivot point.

15. A motorvessel drive as claimed in claim 1, or any one of claims 3to l4asappendantthereto, whereinthefore-and-aftadjusting means is a hydraulic ram or screw actuator acting between the upper point and a point fixed in the vessel.

16. A motor vessel as claimed in any preceding claim, wherein the lifting or lowering means comprises a hydraulic ram or screw actuator acting between the vessel or a member fixed thereto and an intermediate pointoftheupperorthe lowerlink.

17. A motor vessel drive substantially as hereinbefore described with reference to the accompanying drawings.